Question: Access to message_queue management functions

[truschival]

• OS and version used: Linux

• SDK version used: 1.2

Description of the issue question:

Somewhat related to #427. When the connection is (temporarily) I would like to discard older messages or limit the lifetime of messages in the queue.
I have found functions in azureiot/message_queue.h that seem to offer what I am looking for. Unfortunately all functions require a MESSAGE_QUEUE_HANDLE* message_queue argument and I have no idea how I can obtain this handle after/during/between call of IoTHubClient_CreateFromConnectionString and IoTHubClient_SendEventAsync.

Is there any way to access the message_queue?
If not, could you please give me a pointer where to look for limiting the number of queued message and discarding old messages?

Thanks in advance.

[ewertons]

Hi @truschival ,

message_queue is an internal component used in one of the modules within the Azure IoT C SDK.
As we evolve the code we eventually work on individual modules to refactor/advance the code. That's a continuous and independent process, and some modules might use new tools/libraries while others await for their time to enjoy improvements like message_queue.

We do not plan on exposing it though.

You can always limit the overall time a message stays on the queue by calling _SetOption and using option "telemetry_event_send_timeout_secs" (for AMQP; takes size_t* value). MQTT transport does not expose a way to control the maximum queue time.
None of the queues have size caps, so that is not configurable as well.

[ewertons]

@truschival ,
we will close this issue but please feel free to reopen it if you would like to follow up on the question.

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[tameraw]

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